Medical termination for pregnancy in early first trimester (≤ 63 days) using combination of mifepristone and misoprostol or misoprostol alone: a systematic review

BACKGROUND: A wide range of drugs have been studied for first trimester medical abortion. Studies evaluating different regimens, including combination mifepristone and misoprostol and misoprostol alone regimens, show varying results related to safety, efficacy and other outcomes. Thus, the objectives of this systematic review were to compare the safety, effectiveness and acceptability of medical abortion and to compare medical with surgical methods of abortion ≤63 days of gestation. METHODS: Pubmed and EMBASE were systematically searched from database inception through January 2019 using a combination of MeSH, keywords and text words. Randomized controlled trials on induced abortion at ≤63 days that compared different regimens of medical abortion using mifepristone and/or misoprostol and trials that compared medical with surgical methods of abortion were included. We extracted data into a pre-designed form, calculated effect estimates, and performed meta-analyses where possible. The primary outcomes were ongoing pregnancy and successful abortion. RESULTS: Thirty-three studies composed of 22,275 participants were included in this review. Combined regimens using mifepristone and misoprostol had lower rates of ongoing pregnancy, higher rates of successful abortion and satisfaction compared to misoprostol only regimens. In combined regimens, misoprostol 800 μg was more effective than 400 μg. There was no significant difference in dosing intervals between mifepristone and misoprostol and routes of misoprostol administration in combination or misoprostol alone regimens. The rate of serious adverse events was generally low. CONCLUSION: In this systematic review, we find that medical methods of abortion utilizing combination mifepristone and misoprostol or misoprostol alone are effective, safe and acceptable. More robust studies evaluating both the different combination and misoprostol alone regimens are needed to strengthen existing evidence as well as assess patient perspectives towards a particular regimen.